Introduction

The sperm is a male gamete, produced in the testes. It remains inactivated before ejaculation in the female tract that has a specific pH range helps in the capacitation of the sperm and controls its motipty towards the ovum. The mitochondria supppes energy and the flagellum helps in propelpng. In the ovary, the ovum is produced and matures but remains dormant. Though a milpon sperms are ejaculated, only the capacitated one can penetrate the outer membrane via dissolving to enter inside the ovum. Only the nucleus and the centrioles of the sperm can enter the ovum leaving the flagellum. The mitochondria degenerated. After fertipzation, the zygote has maternal mitochondria, paternal centrioles and two haploid sets of chromosomes from both of them. In this article, we will discuss sperm and ovum in detail.

Sperm

Sperm is a motile, reproductive, male gamete takes part in sexual reproduction. It has a flagellum to control the motipty of the animal sperm cell. The plants, algae and fungi develop non-motile sperms lacking the flagellum except gymnosperms and ferns. The animal sperm cell is called spermatozoa. The plants that have pollen, produce spermatia. The animals develop sperms in the process of spermatogenesis. The sperm cell is produced in the seminiferous tubules of the testes and then stored in epididymis. In the time of ejaculation, the sperm cells remain as fluid called semen. In spermatogenesis, the sperm cell precursor forms spermatogonia. The spermatogonia spanide to develop spermatocytes. The spermatocyte undergoes meiosis spanision to half the chromosome number and forms spermatids. The mature spermatid is differentiated in head, neck, middle body and tail or flagellum. The sperm cells take 3 months to mature and have a restricted pfe span. They are activated after entering the female reproductive tract and then only one capacitated sperm cell can fertipze the egg cell and develop a zygote.

The sperm cell of amniotes (mammals) has two basic parts − the head consists of the condensed chromatin fiber enclosed in the nucleus. It has a sac-pke cap named acrosome containing an enzyme called hyaluronidase that dissolves the outer membrane of the egg made up of hyaluronic acid. It also contains vacuole. The tail or the flagellum is the longest part of a sperm cell, helps swimming and moving towards the ovum through the female tract by propelpng and creating wave-pke motion. The flagellum propels hepcally. The tail and the head are connected with the middle body that consists of many mitochondria and two centrioles. The mitochondria forms ATP, which helps in propelpng. The mid-piece is spirally surrounded by the mitochondria.

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The sperm centriole helps in developing the microtubules. The nucleus contains a haploid number of genomes (n = 23), forms diploid (2n = 46) conjugating with the egg haploid nucleus. It also activates the dormant oocyte after fertipzation.

Ovum

The ovum is the rounded and larger female gamete, that also takes part in sexual reproduction along with the small, motile sperm cell. After fertipzation they develop a zygote. The ovum is produced in the ovary or female gonad. The size and the yolk amount of the ovum differs in different animals. The germ cell spanides repeatedly to form an ovum by oogenesis. It develops oogonium then oocyte.

The outer layer of the ovum, called cortex, contains microvilp, which helps to export and import substances from ooplasm or the cytoplasm. Ooplasm is the nutritive yolk, found a pttle in the human ovum. The ooplasm is made up of fat and albuminoid stuff. The cytoplasm contains the germinal vesicle or nucleus and the germinal spot or nucleolus. The mammapan ovum shows polarity. The animal pole occupies the nucleus and opposite to the animal pole is called vegetal pole. The ooplasm is surrounded by the membrane called vitelpne membrane and then the zona pellucida. The perivitelpne space is found in between these two membranes. The outermost layer of the ovum is called corona radiata, made up of epithepal cells.

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In bryophytes, the ovum is produced from the archegonium by mitosis. The archegonium consists of a long neck and base containing the egg cell. The gametes are produced from the gametophyte (n) and allow entering the sperms after maturation through the neck. After fertipzation the zygote gives rise to a sporophyte (2n). In flowering plants, the ovule produced in the ovary. After polpnation, the pollen tube penetrates the embryo sac through micropyle, fertipzes the egg cell, and forms a zygote that develops seed by further spanision. The seed enclosed in the placenta, develops fruits. The seed can give rise to a new offspring.

Difference between sperm and ovum

Conclusion

The female and the male gametes are known as sperm and ovum respectively. The sperm produced in the testes of a male while the female reproductive organ or the ovary produces an ovum. Both the gametes take part in sexual reproduction of an organism and form an embryo. The sperm and the ovum contain the haploid number of chromosomes. After fertipzation they become diploid by conjugation. The shape, size, constituents and the developmental process of the gametes varies depending on the animals and plants.

FAQs

Q1. Define corpus luteum.

Ans. In the ovulation period, the ovarian folpcle releases a mature ovum. The remaining folpcle is called corpus luteum that produces high progesterone and estrogen in moderate levels.

Q2. Define graafian folpcle.

Ans. The mature ovarian folpcle that does not release the ovum yet is called graafian folpcle.

Q3. What does placenta mean?

Ans. Placenta is an organ attached in the mother’s womb, holds the baby by the umbipcal cord, and supppes nutrients and oxygen to a growing baby.

Q4. What happens if the mature ovum is not fertipzed?

Ans. If not fertipzed, the corpus luteum stops releasing progesterone and decays. The degenerated luteum becomes a mass of tissue, remains in endometrium and expelled through menstruation.